Electrical components and methods and systems of manufacturing electrical components

ABSTRACT

A method of manufacturing an electrical component includes providing an electrically insulating substrate having an outer surface, applying a coated structure on the outer surface and irradiating the coated structure with an electron beam to form an electrical conductor on the substrate. The irradiating may include heating the coating layer to melt the coating layer to form the electrical conductor. The coating layer may have a low binder concentration and a high metal concentration. The irradiating may include vaporizing substantially all the binder leaving a substantially pure metallic layer to form the electrical conductor. The coating layer may be irradiated until non-metallic material of the coating layer is completely removed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/710,365 filed Oct. 5, 2012 titled ELECTRICAL COMPONENTS AND METHODSAND SYSTEMS OF MANUFACTURING ELECTRICAL COMPONENTS, the subject matterof which is herein incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

The subject matter herein relates generally to electrical components andmethods and systems of manufacturing electrical components.

Electrical components, such as circuit boards, typically have coatinglayers applied to substrates. For circuit boards, the coating layer maydefine a conductive trace or circuit on the circuit board and/or may beused to enhance electrical properties of the electrical components. Thecoating layers may enhance electrical properties such as by enhancingthe conductivity of the electrical component and providing electricalconnections between components which are assembled on the circuit board.

The coating layers are conductive metallic structures applied to thesubstrate. Application of such layers are typically accomplished eitherby deposition of the conductive metallic structures by using masks (e.g.vacuum evaporation, sputtering, chemical vapor deposition, plating) orby printing metallic pastes or inks on the substrate and then asubsequent thermal post-treatment. Problems exist for these conventionalapplication processes. For example, the smallest producible featuresizes of the conductive metallic structures in deposition from a gasphase are limited by the structure sizes of the masks used (usually onthe order of millimeters or greater), and a large part of the materialused will not be utilized for the actual coating and must therefore beexpensively recycled. Additionally, printed and conventionally thermallytreated structures (e.g. in the oven) feature poorer electricalproperties in comparison to pure metals, since the printing requires theaddition of non-metallic additives such as glue, binder or additives toadjust the flow properties necessary for printing. In the thermalpost-treatment these additives are only partially removed from thelayer, causing the coating layer to have poorer electrical propertiesthan coating layers having higher metallic contents, such as thoseapproaching pure metal. Additionally, thermal stress during thedeposition or during the thermal treatment is problematic. Some methods,such as MID (molded interconnect device) and LDS (laser directstructuring), use special polymers which contain metal catalysts. Use ofspecialty materials in such processes is expensive and the chemicalcoating process can take a very long time.

A need remains for methods and systems of manufacturing electricalcomponents that are cost effective and produce high quality electricalcomponents.

BRIEF DESCRIPTION OF THE INVENTION

In one embodiment, a method of manufacturing an electrical component isproviding an electrically insulating substrate having an outer surface,applying a coated structure on the outer surface and irradiating thecoated structure with an electron beam to form an electrical conductoron the substrate. The irradiating may include heating the coating layerto melt the coating layer to form the electrical conductor. The coatinglayer may have a low binder concentration and a high metalconcentration. The irradiating may include vaporizing substantially allthe binder leaving a substantially pure metallic layer to form theelectrical conductor. The coating layer may be irradiated untilnon-metallic material of the coating layer is completely removed.

Optionally, the coating layer may be printed directly on the outersurface of the substrate and the coating layer may include metalprecursors. The irradiating may chemically reduce the metal precursorsto metals to form the electrical conductor. The irradiating may includereacting the metal precursors with the electrons of the electron beam totransform the coating layer.

Optionally, the method may include preheating the coating layer to atemperature below a melting point of the coating layer prior toirradiating the coating layer. The irradiating may heat the coatinglayer to a temperature above the melting point of the coating layer.Optionally, the method may include irradiating different portions of thecoating layer differently to form a resistor in the electricalconductor. The irradiating may include controlling operating parametersof the electron beam based on the properties of the coating layer.Optionally, the coating layer may be electrically grounded during theirradiating process.

In another embodiment, an electrical component is provided including asubstrate having an outer surface and a coating layer selectivelyapplied to the outer surface. The coating layer is configured in apre-processing state and in a post-processing state after irradiatingwith an electron beam. The coating layer is transformed from thepre-processing state to the post-processing state. An electron beam atleast partially penetrates the coating layer during the irradiatingprocess to transform the coating layer. Optionally, a non-metallicmaterial content of the coating layer may be higher at thepre-processing state than the post-processing state. The non-metallicmaterial may be removed during the irradiating process by the electronbeam. The coating layer may have a low binder concentration when appliedto the substrate, and substantially all of the binder may be removedduring the irradiating process by the electron beam.

In a further embodiment, an electrical component forming system isprovided including a chamber, an irradiation source generating electronbeams and a substrate positioned in the chamber. The substrate has acoating layer selectively applied to the substrate. The electron beamsat least partially penetrate the coating layer to form an electricalconductor on the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an electrical component being processed to form anelectrical conductor on a substrate.

FIG. 2 illustrates a circuit board manufactured using an electron beamto irradiate selectively deposited coating layers to form electricalconductors in the form of conductive traces defining circuits.

FIG. 3 illustrates an electrical component forming system in accordancewith an exemplary embodiment.

FIG. 4 illustrates the interaction of the electron beam with the coatinglayer.

FIG. 5 illustrates a method of manufacturing an electrical component.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments described herein include a method of manufacturing anelectrical component that includes irradiating a coating layer with anelectron beam to form an electrical conductor on a substrate.Embodiments described herein include a system that uses an electron beamto irradiate a coating layer on a substrate to transform the coatinglayer to enhance one or more electrical properties of the coating layer.Embodiments described herein include an electrical component having acoating layer that is transformed by energy from an electron beam toenhance electrical properties of the coating layer to form an electricalconductor.

Embodiments described herein may include an electrical component havingthe form of a circuit board with electrical conductors forming circuitsthereon, the electrical conductors being processed by an electron beam.Other types of electrical components may be manufactured using thesystems and methods described herein.

Embodiments described herein may achieve a high quality electricalconductor by using a non-adiabatic electron beam processing technique.For example, heat may be generated inside the coating layer quickly(e.g. within microseconds), which may transform the coating layer toenhance properties of the coating layer. The heat may be used to melt orremelt some or all of the compounds or materials of the coating layer.In other embodiments, the electrons of the electron beam may react withmaterials of the coating layer to transform the coating layer into aconductive structure. Some of the material of the coating layer may besegregated and/or evaporated by the electron beam during processing totransform the composition of the coating layer. The material used forthe coating layer may be selected to function well with the electronbeam processing.

Embodiments described herein may provide a coating layer and electricalconductor with substantially all residual non-metallic (e.g. organic)material from the paste or ink (used to apply the coating layer to thesubstrate) removed during electron beam processing of the coating layer.The post-processed electrical conductor may be a dense, pore-freemetallic coating. The coating layer may have an initial concentration ofnon-metallic material (e.g. binder) that is lower, even much lower, thanconventional paste (e.g. paste that is processed in a thermal oven). Thecoating layer may have a final concentration of non-metallic material(e.g. binder) that is lower, even much lower, than components made withconventional paste (e.g. processing in a thermal oven).

Embodiments described herein may enhance or select control parameters toachieve a high quality electrical conductor. The interaction of theelectron beam with the applied coating layer and substrate may beconsidered. For example, the interaction of parameters including themetal ink composition, the printing technique (e.g. micro dispensing,screen printing, pad printing, ink jet printing, aerosol jet printing,and the like), and/or the electron beam levels may be considered andbalanced.

Embodiments described herein produce an electrical conductor that mayhave properties necessary to provide stable electro-mechanicalperformance throughout the lifetime of the electrical component. Forexample, the electrical conductor may have a low and stable electricalcontact resistance and good resistance to environmental degradationfactors such as corrosive gas or high temperature exposures. Theelectron beam may be precisely controlled allowing for high spatialresolution of the electrical conductor. The finish of the electricalconductor may be controlled by the electron beam process and thematerials of the coating layer to achieve the desired properties. Forexample, the electrical conductor may have appropriate coating qualitiessuch as layer composition, film thicknesses, roughness, topography,structure, and the like.

FIG. 1 illustrates an electrical component 100 being processed to forman electrical conductor 102 on a substrate 104. During processing, acoating layer 106 is applied on an outer surface 108 of the substrate104. The coating layer 106 is processed by an electron beam 110generated from an irradiation source 112. FIG. 1 illustrates theelectrical component 100 at different stages or states of theprocessing. For example, at 120, the coating layer 106 of the electricalcomponent 100 is shown at a pre-processing state. At 122, the coatinglayer 106 of the electrical component 100 is shown at a processingstate, at which the electron beams 110 at least partially penetrate thecoating layer 106. The coating layer 106 is irradiated to transform oneor more properties of the material of the coating layer 106. The coatinglayer 106 may be transformed into a conductive structure, such as acircuit of the electrical component 100. At 124, the coating layer 106of the electrical component 100 is shown at a post-processing state,after irradiation from the electron beam 110.

In an exemplary embodiment, the substrate 104 may be a non-metallicsubstrate. For example, the substrate 104 may be a plastic material, anFR-4 material, a ceramic material, a glass epoxy material, a foil, asemi-conductor or another type of dielectric material as the basematerial. The substrate 104 may be used to form a circuit board or anantenna structure. With additional reference to FIG. 2, FIG. 2illustrates a circuit board 130, in accordance with an exemplaryembodiment, defining an electrical component 100 manufactured using theelectron beam 110 to irradiate selectively deposited coating layers 106to form electrical conductors 102 in the form of conductive tracesdefining circuits. Optionally, different portions of the coating layer106 may be irradiated differently, such as to form a resistor 131 or aresistor network in one or more of the electrical conductors 102. Theresistors 131 may be formed by processing the electrical conductors 102and/or depositing a coating layer 106 having a high resistance. Theresistors 131 may be incorporated into the electrical conductor 102paths or circuits by variation of the parameters of the electron beam110 during irradiation. No assembly or mounting of resistors to thecircuit board 130 is then necessary.

Returning to FIG. 1, at or prior to the pre-processing state 120, thecoating layer 106 may be applied by printing a conductive or metallicink or paste on the outer surface 108. Optionally, the coating layer 106may be applied directly to the outer surface 108. Alternatively, one ormore layers may be provided between the substrate 104 and the coatinglayer 106. The substrate 104 may be cleaned, de-oxidized, and/orchemically activated prior to printing the coating layer 106 on theouter surface 108, in order to enhance the adhesion of the coating layer106 to the outer surface 108.

In an exemplary embodiment, the coating layer 106 includes metalparticles of various shapes and sizes. The coating layer 106 may includea binder to promote as-printed adhesion and/or a surfactant to preventmetal particle agglomeration (e.g. 1-2 wt %). The coating layer 106 mayinclude a solvent and/or process aids needed for the printingprocess(es). Optionally, the coating layer 106 may contain additionalflux additives (e.g. commercial brazing flux, borax, andpotassium-tetraborate), such as at levels between 1 and 10 wt %. Theflux may be added to adjust a wetting behavior of the coating layer 106during post processing with the electron beam 110. In an exemplaryembodiment, the coating layer 106 may have a high metal concentration(e.g. greater than 50 wt %). In an exemplary embodiment, the metalparticles may be 100% silver particles. Other types of metals may beused in alternative embodiments, such as gold, copper, nickel, tin,zinc, titanium, palladium, platinum, and the like and/or alloys thereofThe coating layer 106 material may include metal precursors which can bechemically reduced to metals. For example, metal salts, metal oxides,and other metal compounds may be used, such as silver chloride, tinchloride, and silver nitrate. The precursors may include metals havinglow melting points, such as tin, zinc, copper, silver, and the like.When using a mixture of metals or alloys, intermetallic structures maybe created during the electron beam processing to achieve desiredcharacteristics or properties for the coating layer 106.

In an exemplary embodiment, the coating layer 106 may be amicrostructure structure of micro particles and/or nano-particles.Optionally, the coating layer 106 may include a mixed powder of solidmetal particles, such as Sn and Ag particles, with a binder, solventand/or flux mixture. The metal particles are melted with the electronbeam 110 to generate a solution where the materials are mixed on theatomic scale. Optionally, the coating layer 106 may be rapidly cooled toquickly solidify the solution to inhibit phase separations and graingrowth. Having good mixture of the materials and having quicksolidification, leads to a fine material microstructure. Optionally,differently sized and shaped metal particle may be used. Precursors,which are reduced to metallic particles during the irradiation andmelting process (e.g. metal salts, metal oxides) may be used.Optionally, a diffusion barrier layer may be provided between thesubstrate 104 and the coating layer 106, such as to reduceinterdiffusion between the material of the substrate 104 and thematerial of the coating layer 106.

The binder concentration may be relatively low (e.g. less than 5 wt %),such as compared to the metal particle concentration. The binderconcentration may be relatively low compared to conventional pastes thatare used in conventional thermal oven post-treatment applications. Thebinder concentration may be between approximately 25 wt % and 5 wt %.Alternatively, the binder concentration may be very low (e.g. less than1 wt %). Examples of binders include dextrins, polyvinyl butyral resins(e.g. Butvar), hydroxypropylcellulose (e.g. Klucel®), but other types ofbinders may be used in alternative embodiments. The binder may includeglue or other additives to change a viscosity of the coating materialfor ease of application to the substrate 104.

The coating layer 106 may be applied by one of various differentprinting techniques, such as screen printing, pad printing, ink jetprinting, aerosol jet printing, micro dispensing, spin coating, a wipingapplication and the like. Other application techniques other thanprinting may be used in alternative embodiments to apply the coatinglayer 106 to the substrate 104. For example, the coating layer 106 maybe applied by powder coating, spraying, dip immersion or otherprocesses. The application technique may selectively apply the coatinglayer 106 to the substrate 104, such as along a predetermined circuittrace path. The printing technique may allow for a standardized patternto be printed on the substrate 104, and the printing may be done in abatch printing application or a continuous reel printing application.The printing technique may be chosen according to the smallest structuresizes of the paste or ink, the layer thicknesses being applied, thecomposition of the coating layer material, and the like.

With additional reference to FIG. 3, FIG. 3 illustrates a electricalcomponent forming system 140 used to irradiate the electron beam 110 atthe electrical component 100 in accordance with an exemplary embodiment.The system 140 may be an electron beam micro welder capable of producingthe electron beam 110. The processing may be performed in a vacuumchamber 142. The power of the irradiation source 112 may be controlledduring processing. The energy density of the electron beam 110 may becontrolled during processing. The deflection speed of the electrons maybe controlled during processing. The maximum acceleration voltage may becontrolled during processing. The maximum electron beam current may becontrolled during processing. The beam focus spot size and depth on thetarget may be controlled during processing. The electron beam 110 may becontrolled based on properties of the deposited layer (e.g. layerthickness, layer composition) and the material properties of the coatinglayer 106 (e.g. density, thermal conductivity, chemical composition).The coating layer 106 and/or the substrate 104 may be heated to atemperature below the melting point to change characteristics of thelayer(s) by reacting materials and/or sintering the layer(s).

The system 140 may be equipped with both a backscatter electron and asecondary electron detector which can be used to produce electron beamimages of the work piece, similar to a Scanning Electron Microscope(SEM). The images can be viewed live on a screen or saved using acomputer. The system 140 may include software to control the functionsof the irradiation source 112, such as to program the electron beam 110to scan defined paths over the sample or to irradiate defined patterns.The electron beam paths may be sweeping paths, scanning paths, spiralpaths or other irregular paths. The software may allow synchronousmovement of the electron beam 110 with the irradiated sample, such as acontinuously moved reel. In such a way, a continuous remelting processis possible. Optionally, the system 140 may include a heat sink, such asa thick aluminum plate heat sink having a high thermal mass andpositioned in good thermal contact with the target.

FIG. 4 illustrates the interaction of the electron beam 110 with thecoating layer 106. The electron beam 110 is focused internal of thecoating layer 106. The electron beam 110 at least partially penetratesthe coating layer 106. In an exemplary embodiment, a beam focus spot 150is in the coating layer 106 rather than in the substrate 104.Irradiation or heating of the substrate 104 is limited by having theelectron beam 110 focused on the coating layer 106. The electron beam110 is used to irradiate the material of the coating layer 106 toachieve electrical conductivity within the coating layer. As theimpinging electrons of the electron beam 110 are scattered by thematerial of the coating layer 106, kinetic energy of the electrons isconverted into heat energy. The scattering probability may be dependenton the energy of the electrons, on the density of the irradiatedmaterial of the coating layer 106, on the beam focus depth, and thelike. Optionally, the penetration depth of the electron beam may bebetween 0.5 μm and 20 μm. In an exemplary embodiment, a characteristicof the energy dependence of the scattering probability is that themaximum of the generated heat density does not lie at the surface of thematerial but at about ⅓ of the penetration depth. Heat is generated notonly at the surface but inside the material of the coating layer 106. Apart of the electrons are reflected or re-emitted from the coating layer106. Such electrons can be utilized to generate in-situ SEM picturesduring irradiation, such as to control the irradiation process via afeedback control system.

The power of the heat which is generated is dependent on the electroncurrent for a fixed acceleration voltage. The product of theacceleration voltage and the beam current gives the power of the beam.The power can be adjusted by controlling the electron current and/or theacceleration voltage. Another parameter that may be adjusted to controlthe irradiation process is the duration of irradiation at or near a spotof the coating layer 106. The printed material of the coating layer 106melts if the generated heat exceeds the thermal energy needed to heatthe material to its melting point and the latent heat of fusion of thematerial. Having the heat energy focused in the coating layer 106, asopposed to the substrate 104, generates heat and melting of the coatinglayer 106 very quickly. Optionally, the substrate 104 may act as a heatsink to quickly dissipate heat from the coating layer 106 afterirradiation enabling high cooling rates of the molten film. Quickheating and cooling rates may affect the properties of the electricalconductor formed by the coating layer 106. For example, the hardness ofthe electrical conductor may be higher with quick heating and cooling asopposed to slow heating and cooling of the coating layer 106, as istypical of thermal curing in a thermal oven where the substrate 104 isheated in addition to the paste. Additionally, more heat energy isneeded to heat the paste in a thermal oven because the substrate isheated in addition to the paste. Optionally, since the heat can begenerated primarily or only in the coating layer 106, the use ofthermally sensitive substrates 104 may be possible. The quick heatingand cooling of the coating layer 106 may avoid heating of the substrate104 by heat conduction.

Since the binders typically have a mass density an order of magnitudelower than the metal particles in the coating layer 106, the volumepercentage of the binders in the coating layer 106 are even higher. Forinstance, a conventional paste typical for use in an application curedin a thermal oven is a 90Ag/10Mo material with 23 wt % Butvar binder,which is a high binder concentration and is borderline very high binderconcentration. Such conventional paste has a binder volume fraction ofapproximately 75%. The high or very high binder concentrations ofconventional pastes is needed to securely fix the printed structuresonto the substrate and the binder remains post thermal treatment usingconventional thermal ovens.

In an exemplary embodiment, for processing with the electron beam 110,the coating layer 106 does not require such a high binder content as thebinder is only needed to keep the printed coating layer 106 adhered tothe substrate 104 long enough to transfer the substrate 104 to theelectron beam 110 for irradiation. For example, a binder content may beapproximately 1 wt %, greatly reducing the volume percentage as well.After melting, the coating layer 106 is dense and has good adhesion tothe substrate. In an exemplary embodiment, the binder is intended to besubstantially entirely removed from the coating layer 106 during theirradiation process, such as by evaporation or by decomposition. Using alow concentration of binder in the coating layer 106 allows quicker andmore thorough evaporation or removal of the binder during irradiation. Abinder having properties such as high paste quality, high printed filmadhesion, film quality of the coating layer 106 after irradiation (e.g.low concentration of carbon residue (char) after irradiation), and thelike are considered when selecting the binder material. Examples ofbinders include dextrins, polyvinyl butyral resins (e.g. Butvar),hydroxypropylcellulose (e.g. Klucel®), but other types of binders may beused in alternative embodiments. In an exemplary embodiment, all orsubstantially all of the binder is irradiated by the electron beam 110and a low amount of carbon residue remains, which may be removed byscraping or another processing technique.

During processing, the operation of the electron beam 110 may vary basedon the type of material of the coating layer 106. For example, theoperation may be different when using pure metallic material versususing metal precursors. In an exemplary embodiment, in the case of thepure metallic components, the post-processing and irradiation of thecoating layer 106 may be controlled by adjusting the energy density andexposure time in such a way that the metal particles sinter or at leastone of the metallic components goes into the melt phase and the coatinglayer 106 fuses into a homogeneous metallic layer. A two-step processwith sintering and subsequent melting is possible in some embodiments.The non-metallic components (e.g. the binder) are segregated orvaporized leaving the pure metallic layer. In an exemplary embodiment,in the case of the metal precursors, the post-processing and irradiationof the coating layer 106 is controlled by the energy density andexposure time in such a way that the metal precursors are chemicallyreduced to metals, either indirectly by the heat input into the coatinglayer 106 or directly by interaction of the metal precursors with theelectrons of the electron beam 110. The non-metallic components (e.g.the binder) are segregated or vaporized leaving the metallic layer. Thecoating layer 106 may transform into a homogeneous metallic layer whenthe precursors are chemically altered by the electron beam 110.

The thermal energy generated by the electron beam 110 inside the coatinglayer 106 can be controlled by adjusting parameters of the electron beam110. At low heat energies and long irradiation times, the coating layer106 may be only partially melted and may not bond to the substrate 104.At low heat energies and long irradiation times the particles of thecoating layer 106 may be only sintered and not completely melted. Insuch situations, the coating layer 106 may not adhere well to thesubstrate 104 and may be easily displaced mechanically over time. At lowheat energies but short irradiation times, portions of the coating layer106 may be removed by the electron beam, such as by splattering away thematerial upon irradiation. At higher energies, large dewetted drops andthree dimensional islands may remain, which is undesirable. At evenhigher energies, such as when the energy is too high, the substrate 104may melt in addition to the coating layer 106, which provides a poorerelectrical interface. The energy level of the electron beam 110 shouldbe controlled to achieve melting of the coating layer 106 while havinggood covering of the substrate 104 and without excessive damage to thesubstrate 104.

During use, particle blowing or spattering of the coating layer 106 mayoccur at any energy level. Several physical effects explain the effectof metal particle blowing: a) transfer of momentum, b) electrostaticeffects, c) electrodynamic effects, and d) thermodynamic effects. Toreduce particle blowing, the amount of non-metallic components may bereduced or minimized, since the less filler there is between theparticles, the higher the number of conductive paths between theparticles there are to ‘bleed off’ excessive charge to ground. To reduceparticle blowing, the coating layer 106 may be preheated such that lowerbeam power is required before the actual melting. For example, thecoating layer 106 may be preheated to a temperature below the meltingpoint of the coating layer 106, such as in a thermal oven, using theelectron beam, or otherwise. During the irradiation process, the coatinglayer 106 is then further heated to a temperature above the meltingpoint of the coating layer 106. To reduce particle blowing, largerparticle sizes of the material of the coating layer 106 may be used orparticles of irregular (non-spherical) shapes may be used to reduceeffects of particle blowing, since more mechanical contacts between theparticles could increase the forces to move particles relative to eachother, as well as possibly creating more conductive paths. To reduceparticle blowing, the scanning or irradiation pattern may be selected toheat the material of the coating layer 106 indirectly via heatconduction, such as through the substrate 104. To reduce particleblowing, the material composition of the coating layer may have a highmetal particle density and/or low porosity to increase the electricaland heat conductivity.

To avoid potential electrical charging of the substrate 104 duringirradiation with the electron beam 110, the coating layer 106 may begrounded. To avoid potential electrical charging of the substrate 104during irradiation with the electron beam 110, the electron beam 110 maybe operated at low accelerating voltages to increase electron emission.To avoid potential electrical charging of the substrate 104 duringirradiation with the electron beam 110, a light (e.g. UV or laser) maybe used to increase the photoconductivity of the coating layer 106. Toavoid potential electrical charging of the substrate 104 duringirradiation with the electron beam 110, the coating layer 106 may beprocessed at an increased pressure (e.g. with argon partial pressure).

In an exemplary embodiment, the control of the electron beam 110, suchas the amount of thermal energy generated by the electron beam 110, maybe varied along the coating layer 106. For example, by changingoperation of the electron beam 110 along one portion of the coatinglayer 106 as compared to another portion of the coating layer 106 thecharacteristics of the coating layer 106 may be varied. For example,resistors may be incorporated into the electrical conductor paths orcircuits by variation of the parameters of the electron beam 110. Noassembly or mounting of resistors is then necessary. In an exemplaryembodiment, the irradiation source 112 may producing the electron beam110 at a power of approximately 2 kW; however it may be more or less inother embodiments. The electron beam 110 may have an accelerationvoltage of approximately 60 kV; however it may be more or less in otherembodiments. The electron beam 110 may have an electron beam current ofbetween approximately 0.15 mA and 15 mA; however it may be more or lessin other embodiments, such as approximately 40 mA. The beam focus spotsize on the coating layer 106 may be approximately 100 μm; however itmay be more or less in other embodiments, such as between approximately30-50 μm. The electron beam 110 may have an irradiation time durationsof between approximately 12 μs/spot and 1000 μs/spot; however it may bemore or less in other embodiments.

FIG. 5 illustrates a method 200 of manufacturing an electricalcomponent, such as a circuit board, an antenna, and the like. The method200 includes providing 202 an electrically insulating substrate havingan outer surface. The substrate may include an insulative base, such asplastic, glass, ceramic and the like, such as for use in making acircuit board.

The method 200 includes applying 204 a coating layer on the outersurface of the substrate. The coating layer may be a paste or ink. Thecoating layer may be a powder or may have other forms. The coating layerincludes a high concentration of metallic particles to form a highquality electrical conductor, such as a circuit trace or a coating onthe substrate. Optionally, the coating layer may include binder tosecure the coating layer to the substrate. The binder concentration maybe low, with the intention of removing substantially all of the binderduring processing. The coating layer may include precursors, such asmetal oxides or metal salts that are processed at a later step.

The coating layer may be applied 204 by printing the coating layer onthe substrate. For example, the coating layer may be screen printed, padprinted, ink jet printed, aerosol jet printed. The coating layer may beapplied by micro dispensing, spin coating, a wiping application, powdercoating, spraying, dip immersion or other processes. The coating layermay be applied directly to the outer surface of the substrate.Alternatively, other layers may be provided therebetween.

The method 200 includes preheating 206 the coating layer prior to otherprocessing steps, such as processing the coating layer with an electronbeam. The coating layer may be preheated to a temperature below amelting point of the coating layer prior to other processing steps,where the temperature may be increased to a temperature above themelting point of the coating layer.

The method 200 includes electrically grounding 208 the coating layerprior to other processing steps, such as processing the coating layerwith an electron beam. The grounding 208 may reduce sputtering of thecoating layer during processing with the electron beam.

The method 200 includes irradiating 210 the coating layer with anelectron beam to form an electrical conductor on the substrate. Theelectron beam may be spot focused within the coating layer, such as atabout ⅓ to ⅔ of the depth of the coating layer, making it possible togenerate heat not only at the surface of the material but inside thematerial. The irradiation with the electron beam may heat the coatinglayer to melt the coating layer to form the electrical conductor.Optionally, such as when metal precursors are used in the coating layer,the metal precursors may interact with the electrons of the electronbeam during irradiation to transform the coating layer into a conductivestructure. The electron beam may chemically reduce the metal precursorsto metals to form the electrical conductor.

The irradiating 210 may vaporize substantially all the binder ornon-metallic material of the coating layer leaving a substantially puremetallic layer to form the electrical conductor. The coating layer maybe irradiated until the non-metallic material of the coating layer iscompletely removed. The irradiation process may be controlled, such asby controlling operating parameters of the electron beam, based on theproperties of the coating layer, such as the thickness, composition,concentration of binder, and the like. Optionally, different portions ofthe coating layer may be irradiated differently, such as to form aresistor in the electrical conductor. The electrical component may be astructured electrical component. For example, layers of the electricalcomponent may be printed in a structured way and irradiated via anelectron beam to get predefined properties in one or more of the layers.The electrical component may be laminated or printed on or in a way todefine a plane structure. Electron beams may irradiate all or selectedportions of the layered structure, and then excess laminated/printedmaterial may be removed.

The methods and systems described herein of processing a coating layer106 with an electron beam 110 achieve a high quality electricalconductor for an electronic component. The process may be performedwithout wet chemistry and at reduced environmental impact. The metalconsumption for manufacturing the electrical component may be reduced ascompared to other manufacturing techniques. The process achieves highselectivity and precise placement of the coating layer 106. The coatinglayer 106 and electronic component may be processed quickly, and may beprocessed as part of a continuous reel-to-reel system or a batch system.The electrical conductors defined by the processed coating layer 106provide improved properties compared to standard procedures. Forexample, the conductors may have increased electrical conductivity,increased thermal conductivity, better corrosion resistance, increasedhardness, and the like.

It is to be understood that the above description is intended to beillustrative, and not restrictive. For example, the above-describedembodiments (and/or aspects thereof) may be used in combination witheach other. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the inventionwithout departing from its scope. Dimensions, types of materials,orientations of the various components, and the number and positions ofthe various components described herein are intended to defineparameters of certain embodiments, and are by no means limiting and aremerely exemplary embodiments. Many other embodiments and modificationswithin the spirit and scope of the claims will be apparent to those ofskill in the art upon reviewing the above description. The scope of theinvention should, therefore, be determined with reference to theappended claims, along with the full scope of equivalents to which suchclaims are entitled. In the appended claims, the terms “including” and“in which” are used as the plain-English equivalents of the respectiveterms “comprising” and “wherein.” Moreover, in the following claims, theterms “first,” “second,” and “third,” etc., are used merely as labels,and are not intended to impose numerical requirements on their objects.Further, the limitations of the following claims are not written inmeans—plus-function format and are not intended to be interpreted basedon 35 U.S.C. §112, sixth paragraph, unless and until such claimlimitations expressly use the phrase “means for” followed by a statementof function void of further structure.

What is claimed is:
 1. A method of manufacturing an electricalcomponent, the method comprising: providing an electrically insulatingsubstrate having an outer surface; applying a coated structure on theouter surface; and irradiating the coated structure with an electronbeam to form an electrical conductor on the substrate.
 2. The method ofclaim 1, wherein said irradiating the coating layer comprises heatingthe coating layer to melt the coating layer to form the electricalconductor.
 3. The method of claim 1, wherein the coating layer includesmetal precursors, said irradiating the coating layer comprisesirradiating the coating layer to chemically reduce the metal precursorsto metals to form the electrical conductor.
 4. The method of claim 1,further comprising preheating the coating layer to a temperature below amelting point of the coating layer prior to irradiating the coatinglayer, said irradiating the coating layer comprises heating the coatinglayer to a temperature above the melting point of the coating layer. 5.The method of claim 1, wherein said applying a coating layer comprisesapplying a coating layer having a combination of binder and metalconcentrations, said irradiating the coating layer comprises vaporizingsubstantially all the binder leaving a substantially metallic layer toform the electrical conductor.
 6. The method of claim 1, wherein saidapplying a coating layer comprises applying a coating layer having ametal precursor, said irradiating the coating layer comprises reactingthe metal precursors with the electrons of the electron beam totransform the coating layer into a conductive structure.
 7. The methodof claim 1, wherein said irradiating the coating layer comprisesirradiating different portions of the coating layer differently to forma resistor in the electrical conductor.
 8. The method of claim 1,wherein said irradiating the coating layer comprises controllingoperating parameters of the electron beam based on the properties of thecoating layer.
 9. The method of claim 1, wherein said irradiating thecoating layer comprises irradiating the coating layer until non-metallicmaterial of the coating layer is completely removed.
 10. The method ofclaim 1, wherein said applying a coating layer comprises printing thecoating layer directly on the outer surface of the substrate.
 11. Themethod of claim 1, further comprising electrically grounding the coatinglayer during the irradiating process.
 12. An electrical componentcomprising: an electrically insulating substrate having an outersurface; a coating layer selectively applied to the outer surface, thecoating layer being configured in a pre-processing state and in apost-processing state after irradiating with an electron beam, thecoating layer being transformed from the pre-processing state to thepost-processing state, wherein an electron beam at least partiallypenetrates the coating layer during the irradiating process to transformthe coating layer.
 13. The electrical component of claim 12, wherein anon-metallic material content of the coating layer is higher at thepre-processing state than the post-processing state, at least some ofthe non-metallic material being removed during the irradiating processby the electron beam.
 14. The electrical component of claim 12, whereinthe coating layer has a low binder concentration when applied to thesubstrate, substantially all of the binder being removed during theirradiating process by the electron beam.
 15. The electrical componentof claim 12, wherein the material of the coating layer is mixed on ananometer scale during the irradiating process by the electron beam. 16.The electrical component of claim 12, wherein the substrate isnon-metallic, the coating layer being printed on the substrate andprocessed with the electron beam on the substrate.
 17. The electricalcomponent of claim 12, wherein the electron beam is used to irradiatethe material of the coating layer to achieve electrical conductivitywithin the layer.
 18. An electrical component forming system comprising:a chamber; an irradiation source generating electron beams; anelectrically insulating substrate positioned in the chamber, thesubstrate having a coating layer selectively applied to the substrate,the electron beams at least partially penetrating the coating layer toform an electrical conductor on the substrate.
 19. The system of claim18, wherein the coating layer is configured in a pre-processing stateand in a post-processing state after irradiating with the electron beam,the coating layer being transformed from the pre-processing state to thepost-processing state, wherein an electron beam at least partiallypenetrates the coating layer during the irradiating process to transformthe coating layer.
 20. The system of claim 18, wherein the coating layerhas a low binder concentration when applied to the substrate,substantially all of the binder being removed during the irradiatingprocess by the electron beam.